**Question:** True/false. NCCT is the initial investigation of choice in any stroke patient. Hyperdense MCA sign is a sign of acute infarct on MRI. Thrombolysis is contraindicated in haemorrhagic stroke. DWI is the most sensitive sequence for acute stroke. Window period for iv thrombolysis in acute ischemic stroke is 4.5 hours according to ECASS-III trial.

**Core Concept:** In the context of stroke management, it is essential to understand the role of various imaging modalities and thrombolysis guidelines.

**Why the Correct Answer is Right:**

1. NCCT (Non-Contrast Computed Tomography) is a rapid, widely available, and cost-effective imaging modality often used as the initial investigation in stroke patients. NCCT helps in detecting hemorrhage, intracranial mass effect, and early signs of cerebral edema.

2. Hyperdense Middle Cerebral Artery (MCA) sign on NCCT indicates a large vessel occlusion with ischemic stroke, making MRI (Magnetic Resonance Imaging) more suitable for further evaluation. MRI provides better resolution and contrast between normal and abnormal tissue, allowing for more accurate diagnosis and excluding alternative diagnoses.

3. Thrombolysis is a treatment option for ischemic stroke patients with specific criteria. In the case of haemorrhagic stroke, thrombolysis is contraindicated due to the risk of worsening the haemorrhage and causing further brain injury or even death.

4. DWI (Diffusion-Weighted Imaging) is a highly sensitive MRI sequence in detecting acute ischemic stroke, particularly in the early stages. It helps in identifying the affected tissue and assessing the extent of the infarct.

5. The ECASS-III trial established the iv thrombolysis (intravenous thrombolysis) window period for acute ischemic stroke patients as 4.5 hours from symptom onset. This information is crucial for determining eligibility for thrombolysis treatment.

**Why Each Wrong Answer is Incorrect:**

1. Option C (DWI is the most sensitive sequence for acute stroke) is incorrect as DWI is sensitive, but MRI is not always readily available in emergency settings, and NCCT is more widely available, faster, and cost-effective.

2. Option D (ECASS-III trial established the iv thrombolysis window period as 7 hours) is incorrect as the trial actually established the window period as 4.5 hours, not 7 hours.

3. Option E (NCCT is not used in stroke management) is incorrect as NCCT plays a crucial role in stroke diagnosis, particularly in excluding haemorrhagic stroke and detecting intracranial mass effect.

**Clinical Pearls:**

**Core Concept:** Stroke management involves a combination of clinical evaluation, imaging studies, and treatment options, including thrombolysis, depending on the type of stroke and imaging findings.

**Why the Correct Answer is Right:**

NCCT is an essential tool for initial stroke assessment, particularly in excluding haemorrhagic stroke and detecting intracranial mass effect. MRI (Magnetic Resonance Imaging) is more sensitive but not always readily available in emergency situations.